Powdered metal in engine
 

Engine is a 535.Allpontiac block,HP heads,10.5 compression.55 mm roller cam Redzone lifters.We put it together a couple of years ago and it sat till 2 weeks ago.Turned over fine by hand and with starter.Just after firing it locked down.We tore it down and found powdered metal in four cylinders.Enough to wedge the piston against the head.The metal was all the way from carb to exhaust ports.We thought the cylinder walls must have rusted from sitting so long and the rings scraped it off.Pulled the engine,went back through it from start.Everything looked good just needed cleaning.Put the engine back in the car and it looks like it did the same thing.Locked up just after firing.Pulled the intake and found black powdered metal everywhere.
We didn't put water in till just before trying to crank it.There was no water in the cylinders.
Any ideas?Cleaned the fuel cell and line before the first attempt.Can't figure it out.Getting frustrated.

when you say carb to exhaust ports, you finding it in the bowls, or in the filter?? sucking anything in from exturnal source?? underside of hood, cowl area?? Im assuming that you had it apart did you get it all cleaned out good?? As per rusting on the cylinder walls. If you had it in an unheated garage stored. Condesation can form in the cylinders with weather changes if cylinder walls arnt coated. Had that happen to a block i had stored had them wiped down with oil and in a bag for a few years. Ended up with surface rust streaking, had to hone out.

Powdered metal in engine
 

There is none inside the carb.It starts in the intake just below.We took the engine out and started from scratch.Honed vatted, cleaned and cleaned some more.Took the heads apart,valve job done,complete rebuild.Put the engine together Wednesday.It sat in the engine room till Friday night when we installed it.Cranked Saturday morning.It's was inside a machine shop the whole time.Never taken outside.There is enough metal to pile up on the pistons and lock them against the heads.There is nothing on top of the engine to be a source.No hood or air cleaner.Could it pull that much metal from rusty headers?We thought it was cylinder wall rust the first time.There is no way it could be the second time.

Have the heads been resurfaced lately? I had my E's resurfaced down .02 and found freaking metal everywhere! Luckily I looked them over before installing them.

Good thought but it can't be heads.The metal is iron.Everything was cleaned thoroughly prior to assembly.I'll post some pictures later today.

Let me get this straight. It sat for 2 years, and locked up upon start. You pulled it apart and cleaned everything, honing the cylinders and going through the heads, etc. and let it sit for two days, only to experience the same thing again? And this "metal" is showing up from carb to exhaust ports? Someone has sabotaged your engine.

No one has been near it.I assembled it.They would have had to pour it through the carb and it's not there.

i have seen exhaust reversion do some funny stuff. i built a set of headers once with the little rings that hooker used to sell. one of them came apart inside the primary tube and found it's way into a cylinder.
could it be rust from inside the header tubes? ever dropped an uncoated header on the ground after it has been sitting for a while? lots of loose stuff in there.

Was thinking the same thing......:(

What does the oil look like? Are you certain it is metal powder? Are the 4 contaminated cylinders on the same side of the motor? Do they have any relationship...front 4...firing order...or random. Was it the same 4 both times?

Sounds like you have a pretty tight quench area if powdered metal stops the engine from turning over. What do the rings look like, are the pistons scuffed? It sounds like way to rough of a cylinder wall finish to me, prematurely wearing the rings out. The new rings that we have today will not tolerate a very rough cylinder finish like the rings we use to get years ago. I just had an engine here that had similar issue, but it did not lock up. What we seen was excessive blow by to the point that it blew the dipstick out. This is about the tenth time I have had an engine come into my shop with this problem in the last 5 years. Every time it came down to cylinder wall finish, and every time it was the same old story. I just had the engine rebuilt less than 200 miles ago and this started.


Don Johnston
DCI MOTORSPORTS INC.
330-628-3354 cell
330-850-5050 shop
Designer of the DCI Tiger heads and the NEW DCI Ram Air V heads!!!!

I can't imagine what could be making that much metal and not leave telltale signs in the engine. If it's NOT being poured down the intake, it's gotta be coming from a wear surface inside the engine. I would expect that the source would show gouges and areas where metal is missing. Piston/ring wear should show scuffed pistons, scuffed cylinders and rings with big end-gaps. Big wear surfaces should be painfully apparent.

If no source is found, then check the exhaust. Could be a bird nest, rust or a bunch of crap in the headers, exhaust pipes or mufflers.

Anything that you had coated on the engine? Intake, pistons?

metal in engine
 

Took the engine apart this morning.Pile of rusty metal in 3.4,7,8.The cylinder walls look good.I'm pretty sure it's coming back from the headers.There was a pile of rust in the floor at the end of the headers that looks just like what was in the engine.I didn't know that could happen.

Sorry 1,2,5,6.

After seeing those pic's, I would say most definitely from the headers. I see your using header wrap, that stuff holds the heat so well that it breaks down the header tubes. It's amazing how debri travels through an engine before it gets spit out. I have seen carb nuts get dropped into intakes and go through all 8 cylinders. Crazy and weird stuff. What is that thing that looks like a stick laying on the piston?



Don Johnston
DCI MOTORSPORTS INC.
330-628-3354 cell
330-850-5050 shop
Designer of the DCI Tiger heads and the NEW DCI Ram Air V heads!!!!

I assume it only ran a second or two? I'm thinking it aspirated the rust from the exhaust while cranking or as it started to run. Black and red debris would be carbon and rust from the inside of the header tubes.

What are the specs on the cam? I would expect that it would have to be a fairly large cam with a decent amount of overlap (or early exhaust opening event) to do something like this. It would be a huge amount of reversion to suck that much crap out of the exhaust.

Was the block pressure tested and magged for cracks? Only other thing I can think of is rust/water from the cooling system getting into the cylinders.

What is the exhaust system? Open headers?? How old? Shine a light in there and there should be a lot of rust.

Yes the headers are very rusty inside.I don't have the cam specs with me but it is big.There was no water in the cylinders until I took the heads off.Block and heads were pressure tested.I didn't notice that stick looking thing until I looked at the pictures.I think it's a piece off the gasket.What's the best way to clean rust out of headers?

What's the best way to clean rust out of headers?


sand or media blast and maybe then have them coated.

cleaning
 

I used a pressure washer with a drain cleanout tip on the end of a flex hose was able to run it thru all the pipes both directions. did a nice job.

It is a HUGE bummer to have a fresh 505 all F'ed up due
to some lousy ass HEADERS :mad: :eek:

I hope that you can clean everything up, re-assemble and get back to Pontiyaking with this thing.

Keep us posted on how things go and good luck!~

Why does this reversion happen, is it cam choice?

I get the header idea, but, if it started I would think the exhaust pressure would be mostly in an exhaust direction. Thereby blowing most of the rust out! Reversion when the engine is running is way less than exhaust pressure. We're talking a lot of foreign debris to cause enough build up to fill the quench area.
Not to mention he's finding it in the intake as well. That's a lot of reversion. If he's getting it from the headers he has other problems to make it all the way to the intake. IMO

Well, it's an extreme case, but it's a very large motor. A 535 has a lot of swept area, so it's possible that a strong downward stroke with the exhaust valve open could create a decent amount of exhaust vacuum.

During cranking, if cylinder 1 fires while cylinder 5 exhaust is open, you could get a strong toke on the #5 primary tube.

If a set of headers made me tear a motor down twice, that would be one former set of headers!

It didn't really start.It sounded like it ran through about once then locked down.I'm not happy with those headers,but it's 1200 dollars to get new ones.These are going to get acid dipped,cleaned and coated.We started cleaning them tonight.There was still an impressive amount of loose metal in them.I hope there not rusted through.

Yes, cam profile, head porting, alignment, header design (tubes) can all come into play.

Cant you find another set to try and see if that is the problem?

No.I would have to have another set made for the car.If I can't get these as clean as they need to be that's what I'll do.

http://www.qccoatings.com/

these guys do a great job at a fair price! They generally turn stuff around in 1 week. Plus the coating is supposed to be worth 10 or so.

The old test for a bad intake valve is to hold a piece of paper near the tail pipe and see if it sucks in. Could some bent or burnt valves cause the rust to get sucked in?

When the rust got in the engine it also got under the valves,keeping them from closing.So it could have perpetuated the problem.But it was a fresh valve job with 16 brand new titanium valves before we tried to crank it.

gata,
Agree with others here that the headers are the source of your troubles. We have seen header rust and even fabrication debris left in the tubes do major engine damage. Those look like the heads we did for you a few years back. I have the cam specs if you need them...PM me if necessary.

Man that sucks! Sorry :(

I just got a pep talk on this very subject. I'll be building my own headers for my car in my garage with the help of a friend (25 year Navy fabricator and nuclear certified welder) and I plan on being extremely cautious about this. I'm thinking I may actually spend the extra money for stainless tubing so rust will be less of a factor.

This is the second engine I've heard of sucking in debris through the headers on start up :mad: